Telephone system.



, PATENTED AUG. 16, 1904. v F. R. PARKER. TELEPHONE SYSTEM. APPLIOATIbN. FILED DEO.14, 1903.

N0 MODEL.

' WITNESSES 1 although this is not essential.

UNITED STATES.

FREDERICK R. PARKER,

OF CHICAGO, ILLINOIS.

TELEPHONE SYSTEM. 7

SPECIFICATION forming part of Letters Patent N 0. 767,953, dated August -16, 1904. Application filed December 14, 1903. Serial No- 185,136. (No model.)

To all whom it may concern.-

Be it known that I, FREDERIoK R. PARKER,a citizen of the United States, residing at Ohicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Telephone Systems, of which the following is a full, clear, concise, and exact description, reference being had, to the accompanying drawing, forming a part of this specification. 7 I

My'invention relates to a telephone sys tem, my object being to provide improved means for operating the signaling devices in such a-system.

Itcis customary in a telephone system to employ relays in the line-circuits thereof for operating the line-signals and relays in the plug-cord-connecting circuits for operating the supervisory signals. In this present invention I employ one relay in each line-circuit, the said relay being provided with a double armature and adapted to operate and control both the line-signal and the supervisory signal. Both armatures of the relay preferably operate the same contact-spring,

When both armatures are attracted to the core, the circuit of the line-signal is closed.' When neither armature is attracted, the circuit of the supervisory signal is closed at the relay, and when one armature only is attracted neither of the said signaling-circuits is closed. I employ a Winding in the cord-circuit, which shunts the said relay when connection is made with the line. The relay is preferably of a high re sistance, and the said windingis preferably of a low resistance, thus allowing the said winding to shunt most of the current from the said relay when'they are connected in multiple, as will be hereinafter shown. I

preferably employ two superposed armatures at one end of the relay-core, but do not Wish to confine this invention to such a particular arrangement of the said armatures. One

limb of the calling-telephone line is connected through'the said relay to a central source of electricity, and the other limb of the said line is preferably connected through an impedance-coil to the. said source.

I will more particularly describe my'invention by reference to the accompanying drawing, lllustrat ng same, in which is shown two subscribers lines and the central-station signaling and connecting apparatus.

limb 0 being connected to jack-contacts ffi Limb b is also connected through the windingof relay D to pole' r of battery F. Likewise limb c is connected through the winding of impedance-coil E topole s of battery F. 'Pole 9" of battery F is connected through conductor 2? to spring c' of relay D. Spring 2' normally engages contact but is adapted to disengage contact j and to engage contact 5. Contact j is connected through conductor 9 to jack-contacts e e of the several spring-jacks O O.- a Contact 71 is connected through conductor a, visual lamp on, and conductors o-and p to pole s of battery F. Armature Z of relay D is adapted to disengage spring 2' from contact j when it is attracted, and armaturek is adapted to engage spring c' withcontact 72, when it is attracted. It is understood that when spring c' engages contact it it is disengaged from contact 1'.

The line of subscriber B (shown upon the right of the drawing) is similar to the line of subscriber A, just described, and likecharacters are employed for indicating like parts.

In the plug-cord-connecting circuit the tipcontact of connecting-plug G is connected,

through tip-strand a condenser 9 contact.

spring 7' conductor '0 contact r spring Q2, and tip-strand 622, to the tip-contact of connecting-plug H. The sleeve-contact of connecting-plug G is connected, through sleevestrand condenser if, spring n contact m, conductor 122 contact .53 spring 23 and sleevestrand to the sleeve-contact of connecting-plug H. The third conductor 12 of connecting-plug G is connected, through visual lamp u and conductors w and p, to pole s of battery F. The third conductor a of connecting-plug H is connected, through visual lamp 4) and conductors w and p, to pole s of talking-circuit is connected, through conducbattery F. The tip-strand 66 0f the plugcord IOO tor .1 the winding of impedance-coil I, and conductor t, to pole 0' of battery F. Contact Z? of the plug-cord talking-circuit, separated from the tip-strand (1 by condenser is connected, through conductor 1/, the winding of impedance-coil J, and conductor t, to pole r of battery F. l/Vhen listening-key K is depressed. springs y' and 01? thereof are disengaged from contacts If and m respectively, and engaged with contacts 71 and 0 respectively. Spring also engages contact W. The operators set (not shown in the drawing) is adapted to be bridged from spring Z to contact 0 Contact is for a busy-test circuit. I/Vhen ringing key L is depressed,

I springs g and t thereof are disengaged from contacts r and 5 respectively, and engaged with contacts 19 and 14 respectively. Contacts p and a are adapted to be connected to a source of calling-current. The insulatingpin .2 of listening-key K is secured to springs 1' and Z so as to compel spring Z to operate with spring f If subscriber A desires to talk with subscriber B, he lifts his telephone-receiver from the switch-hook, thereby closing the circuit between'limbs b and 0 of his telephone-line in a manner well understood and allowing current from battery]? to flow through the winding of relay D, limb Z), substation A, limb c, impedance-coilE, and conductor 19. This current traversing the winding of relay D energizes the core thereof and attracts both armatures Z and it thereto. Armature Z being attracted disengages spring t' from contact 1', and armature 7': being attracted engages spring with contact it. Thus the circuit of battery F is closed through conductor t, spring i, contact 71, conductor a, visual lamp on, and conductors o and 11, thereby lighting the visual lamp on, which conveys to the operator the signal for connection. The operator then inserts the answering plug G into a spring-jack C of line A. tion' of the said plug into the said jack closes the circuit of battery F through conductor t, impedance-coil I, conductor m tip-strand a jack-contact cl, limb b of the telephone-line, substation A, limb c, impedance-coil E, and conductor p. It will be readily seen that impedance-coil I forms a shunt around relay D,

and as the resistance of relay D is high compared to the resistance of impedance-coil I the impedance-coil I takes the greater part of the current away from relay D. Relay D is still energized sufficiently to attract armature Z, but not sufficiently to attract armature 71'. Thus armature it falls back to its normal position, and in so doing disengages spring 2' from contact h, thereby breaking the circuit through visual lamp on and extinguishing its signal. Spring 2' does not engage contact 7, as it is held therefrom by armature Z. The operator then depresses the listening-key K, and in so doing bridges her telephone set across The inserthe line of subscriber B is not in use the operator inserts the calling-plug H into a springack C of line B. The insertion of plug ll into a jack 0 of line B closes the circuit of battery F through conductors and :1, visual lamp 1*, conductor jack-contact of line B, conductor a, contact spring i, and conductor t, thereby lighting the visual lamp w, which shows to the operator that subscriber B has his telephone-receiver on the switch-hook. The operator then depresses the ringing-key L in the usual manner, and thereby signals subscriber B in a manner well understood. In depressing the ringing-key L the operator also restores the listening-key K to its normal position. Vi hen subscriber B responds to the call and lifts his telephone-receiver from the switch-hook, he closes the circuit between the limbs of his telephone-line in a manner well understood, and thus closes the circuit of battery F through conductor im pcdance-coil E, limb 0 of his telephone-line, substation B, and limb Z), where the circuit divides and takes two paths back to pole r of battery F, one said path being through the winding of relay D, the other said path being through jack-contact (Z, tip-strand (1*, spring q, contact 1", conductor w, spring contact conductor impedance-coil J, and conductor t. It will be readily seen that impedancecoil J forms a shunt around relay 1), and as the resistance of relay D is high compared with the resistance of impedance-coil J the impedance-coil J takes the greater part of the current flowing through substation B. Relay D is sufficiently energized, however, to attract armature l to the core thereof, and thus disengage spring 1i from contact 1'; but it is not sufiiciently energized to attract armature l' thereof. As spring /Iis disengaged from contact j the circuit through visual lamp w is thereby broken and the said lamp 1) is extinguished. The subscribers A and B are now connected for conversation with each other. WVhen the conversation is completed and subscriber A hangs his receiver on the switchbook he breaks the circuit between the limbs b and c of his line at the switch-hook in a manner well understood, and thereby stops the flow of current from battery F through relay D of line A. Relay D is thus deenergized, and armature Z thereof falls away from the core, thereby engaging spring i with contact j. The engagement of spring i with contact j closes the circuit of battery F through conductor t, spring 1f, contact j, conductor jack-contact a, conductor 7/, visual lamp u, and conductors in and p, and lights the visual lamp 11, thus conveying to the operator the signal for disconnection. When subscriber IOCI B-hangs' his telephone receiver upon the switch-hook, he breaks the circuit of battery F through relayD of line B at his substation,

This

as just described, for subscriber A. causes armature Zof relay D, belonging to the line of subscriber B, to fall away from the core thereof, and thus cause spring 2' to engage contact 3'. The engagement of spring 5 with contact 7' closes the circuit-of battery F through conductor 2?, spring 2', contact 7, conductor g, jack contact e of a spring-jack belongingto line B, strand e visual lamp u, and conductors w and p, and lights the visual lamp 4;, thus conveying signal for disconnection.

When the operator receives both disconnect signals from subscribers A and B, respectively, she withdraws the connecting-plugs G and H from their respective spring-jacks, thereby breaking the circuits through the visual lamps u and u, respectively, and thus extinguishing their signals. All circuits and apparatus are now in their normal condition.

While I'have 'show'n visual lamps for the signaling devices'throughout this invention, 1' wish it to'be understood'that any electricallyoperable signaling device may be used in place claimed 'in a copending application for patenton relay, Serial No. 194,392, filed February 19, 1904.

Having thus described my invention. what I claimas new, and desire to'secure by Letters Patent, is

1. The combination with a telephone-line, of

a source-of electricity, a double-armature relayd'connected from one limb of the line to the sal the other limb of the line to the said source, a signaling device adapted to be operated by the said relay, a second signaling device placed under control of the said relay when connection-is made with the line, means whereby the circuit of the said source is closed through the said relay and impedance-coil, thus operating both armatures of the said relay, and means for shunting thesaid relay when connection is made with the said line, and thereby releasing one armature of the said relay,

substantially as described.

2. The-combination with atelephoneline,of a source of electricity, a double-armature relay connected from one limb of the line to the to the operator the This doublesource,animpedance-coil connected from said -source,each armature of therelay being adapted 'to control a local circuit, means for closing the circuit of the said source through the said relay and a limb of the telephone-line, with a suitable return, thereby operating both armatures of the relay, and means whereby the said relay is shunted by a resistance, thus rendering one armature only thereof, inoperative, substantially as described.

3. The combination with ateleplioneline,of a source of electricity, a double-armature relayconnected from one limb of the line to the said source, an impedance-coil connected from the other limb of the line to the said source, a local circuit for each armature of the relay and controlled thereby, a plug-cord circuit adapted to be connected with the telephoneline, an impedance coil through which the said source of electricity is connected to a strand of the plug-cord-connecting circuit, a

line-signal and a source of electricity in one.

said .local circuit, a supervisory signal and a source of electricity adapted to be connected in the other said local circuit when connection is made with the telephone-line, means for closing the circuit of the first-mentioned source through the said relay and a limb of the telephone-line, with a suitable return, thereby actuating both armatures of the said relay and operating the line-signal, means whereby the cord-circuit impedance-coil is connected as a shunt around the said relay, when connection is made with the line, thereby rendering one of the said armatures inactive and extinguish ing the line-signal, and means for opening the circuit of the telephone-line when connection is made therewith and thereby rendering both armatures of the relay inactive and operating the supervisory signal, substantially as. described.

4. The combination witha telephoneline,of asource of electricity, a relay connected from one limb of the line to the said source, an impedance-coil connected from the other limb of the line to the-said source, a pair of superposed armatures for the said relay, a spring adapted to be operated by either of the said armatures and thereby control two-local circuits, one for each armature, a signalingdevice for each local circuit, means for closing the circuit of the said source through the relay and a limb of the telephone-line, with a suitable return, thereby actuating both armatures thereof, and means for shunting the said relay and thereby releasing one armature only thereof, substantially as described.

5. The combinationv with a telephone-line, of a source of electricity, a relay connected from onelimb of the line to the said source, an impedance-coil connected from the other limb of the line to the said source, a pair of superposed armatures for the said relay, a spring adapted to be operated byeither of' the said armatures and' thereby control two signalingcircuits, one for each armature, a plug-cord necting-eord and adapted to be connected in terminals, of a common source of electricity,

inon source, a signaling-circuit for each a rmature of each relay and controlled thereby, a

plug and connected from the said source to conductor for each plug and connected with ing their armatures, means for shunting the and to the common source, means whereby circuit adapted to be conductively connected with the said line, an impedance-coil through which the said source is connected to a main strand of the plug-cord circuit, a linesignal for one said signaling-circuit, a superl visory signal in circuit with a strand of a con the other said signaling-circuit, when connection is made with the line, and means for operating the said armatures separately or together, for the purpose of operating and controlling the line-signal and supervisory signal, substantially as described.

4 6. In a telephone system, the combination with telephone-lines extending to a central station and terminating in suitable connectiona double-armature relay for each line and connected from a limb thereof to the said comeord-circuit terminating in connecting-plugs and adapted to be connected with the said lines, an-lmpedance-eoil for each connectingeonductors of their respective plugs, a third respective supervisory signals, means for closmg circuits of the said source through the said relays, respectively, and thereby operateircuit for each line and adapted to be completed when connection is made with the said lines, respectively, the said line signaling-circuits and supervisory signaling-circuits being operated by respective armatures of the said relays, a plug-cord circuit adapted to be connected with the said lines, an impedance for each connecting-plug and connected thereto the said impedances form shunts around the said relays, respectively, when connection is made with the said lines, and means for operating the said relays and signals, for the purpose of connecting and disconnecting subscribers lines, substantially as described.

8. The combination with a telephone-line, of a source of electricity, a double-armature relay connected from the line to the source,

a circuit-controlling means adapted to be operated by the armatures, slgnaling devices adapted to be operated by the circuit-controlling means, and means for operating the relayarmatures separately or together and thereby operating the signaling devices.

9. A double-armature relay associated with a telephone-line, a circuit-controlling means adapted to be operated by the armatures, circuits to be opened and closed by the circuitcontrolling means, and means for operating the relay-armatures separately or together.

10. The combination with a telephone-line, of a relay connected thereto, arn'iatures for the said relay, a source of electricity, a signalingcircuit for each armature, a circuit-con trolling means adapted to control the signaling-circuits and adapted to be operated by either armature, and means for operating the said armatures from the said source, separately or together,and thereby controlling the said signaling-circuits, substantially as described.

11. The combination with a telephone-line, of a relay normally connected thereto, the said relay being provided with two armatures, a source of electricity,a signaling-circuit ad apted to be controlled by one armature, a plugcord-eonneeting circuit for the line, a second signaling-circuit adapted to be completed when connection is made with the line, and placed under control of the other armature,and means for operating the relay-armatures from the said source, separately or together, substantially as described.

12. The combination with a metallic telephone-line, of a double-armature relay connected from one limb of the line to a source of electricity, an impedance-coil connected from the other limb of the line to the said source, a member adapted to be operated by both relay-armatures and thereby control two signaling-circuits, a connecting-circuit for the line, means for completing one of the said signaling-circuits when connection is made with the line, means for closing the circuit of the source through the relay and thereby opcrating the armatures thereof, and means for shunting the relay with the connecting-circuit, when connection is made with the line, and thereby rendering one armature only, of the relay, inoperative, substantially as described.

13. In combination, an electrical transmitting-line, an electrically-operable device associated therewith, circuit-controlling means, circuits to be controlled by said means, operable members for said device and adapted to operate said means, one operable member eontinuing the operation of said means from where another operable member le't't oli', and means for operating said operable members one at a time or together.

1 A relay provided with two armatures and connected in circuit with a normally open telephone-line, respective signaling-circuits to be controlled by the said armatu res, a son ree of electricity, the relay armatures being adapted to operate on difl'erent strengths of v winding, during the use of the telephone-line,

and thereby operating the said relay-armatures, substantially as described.

15. The combination with a telephone-line,

of a relay provided with two armatures and connected with the said line, a spring contact member adapted to be operated by either armature, two signaling-circuits controlled by the spring contactmember, one signaling-circuit being open while the other is closed, and means for operating the said armatures :From a source of electricity, one at a time or both together, substantially as'described.

16. A relay provided with a pair of superposed armatures and connected with a telephone-line, a line-signal and a supervisory signal adapted to be operated by the said armatures, one of the said signals being put in condition for operation when. connection is made with the line, and means for operating the said armatures separately or. together, to control the said signals.

17 A relay provided with a pair of super- .posed armatures and connected with a telephone-line, a spring member adapted to be operated by either of the said armatures, sig- 3O naling-circuits adapted to be controlled by the said spring member, and means for operating the relay-armatures, independently or together, during the use of the telephoneline, and thereby operating the signaling-circuits, substantially as described.

18. The combination with a telephone-line, of a relay provided witha pair of superposed armatures and connected with the line, a spring member adapted to be operated by either of the said armatures, two signaling circuits adapted to be controlled by the said spring member, a plug-cord circuit adapted to be connected with the said line, one 'said signalingcircuit being completed through a strand of the pl u'g-cord circuit when connection is made with the line, a source of electricity, means for closing the circuit of the said, source through the said relay and telephone-line, and thereby operating the said armatures, and means whereby the plug-cord circuit shunts the said relay, when connection is made with the line, and thereby releases one armature only and-renders it inoperative, substantially as described.

19. The combination with a telephone-line, of an electrically-operable device normally associated therewith at a central station and provided with operable members for controlling signals, signals adapted to be operated, one being connected for operation when connection is made with the line, and means for operating the operable members separately or together.

20. The combination with a telephone-line,

of an electromagnet normally associated therewith at the central station and provided with operable members adapted to control signalcircuits, signal-circuits adapted to be con-.

operating the said operable members separately or together, to control the said signals.

22. The combination with a telephone line, of a relay associated therewith and provided with armatures, a circuit-controlling means adapted to be operated by either armature, suitable circuits to be controlled by the circuit-controlling means, and means for operating the armatures separately or together.

23. The combination with a telephone-line, of an electrically-operable device associated therewith and provided with operable members, a circuit-controlling means adapted to" be operated by the operable members, suitable circuits to be controlled by the circuit-controlling means, and means ,for operating the operable members separately or together.

24. The combination with a telephone-line, of a double-armature relay associated with the line, a spring-switch adapted to be operated by-either armature of the relay, suitable circuits to be controlled by the spring-switch, and means for operating the armatures separately or together. i

25. The combination with an electrical trans mitting line, of an electrically-operable device associated therewith and provided with operable members, a circuit-controlling means adapted to be operated. by the operable members, suitable circuits to be controlled by the circuit-controlling means, and means for operating the operable members separately or together.

26. The combination with electrical transmitting-lines, of an electrically-operable device for each line and associated therewith, each said device being provided with operable members, acircuit-controlling.means for each device and adapted to be operated by each operable member thereof, suitable circuits for each circuit-controlling means and controlled thereby, a connecting-circuit for the lines, one circuit'for each circuit-controlling means being completed when the said connectingcircuit is connected with the lines, and means for operating the operable members of each device, separately or together.

27. The combination with an electrical transmitting-line, of an electrically-operable device associated therewith and provided with l operable members, a switch common to two l mally associated with a telephone-line at a censignal-circuits and adapted to be operated by each of the operable members, one said signal-circuit being completed when connection is made with the line, and means for operating the operable members.

28. The combination with a telephone-line, of a relay provided with superposed armatures and associated with the line, a springswitch adapted to be operated by each armature, signal-circuits adapted to be controlled by thespring-switch, one signal-circuit being completed when connection is made with the line, and means for operating the armatures, substantially as described.

29. electrically operable device nortral station, and provided with operable members, a signal-controlling means adapted to be operated by the operable members, suitable signals adapted to be controlled by said signal-controlling means, and means for operat ing the operable members, separately or together, to operate the signal controlling means.

In witness whereof I hereunto subscribe my name this 12th day of December, A. .l). 1903.

FREDERICK R. PARKER.

lVitnesses:

R. (Jr. PARKER, W M. F. VIOLETT. 

